Portillo does not face imminent extradition, however. Under Guatemalan law, he must first be tried at home in a separate corruption case before facing charges abroad.

Portillo vows to appeal Wednesday's ruling, saying: "This is not finished yet."

He is charged in a New York federal court with embezzling $1.5 million in foreign donations intended to buy school library books in Guatemala. He allegedly endorsed checks drawn from a New York bank and deposited them in a Miami account.

Portillo was president from 2000 to 2004. He was arrested Jan. 26 on the U.S. extradition request. He denies the charges.